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Variscan to Alpine magmatic activity on the North Tethys active Eurasian margin in the Caucasus region is revealed by ⁴⁰Ar/³⁹Ar ages from rocks sampled in the Georgian Crystalline basement and exotic blocs in the Armenian foreland basin. These ages provide insights into the long duration of magmatic activity and related metamorphic history of the margin, with: (1) a phase of transpression with little crustal thickening during the Variscan cycle, evidenced by HT-LP metamorphism at 329–337Ma; (2) a phase of intense bimodal magmatism at the end of the Variscan cycle, between 303 and 269Ma, which is interpreted as an ongoing active margin during this period; (3) further evolution of the active margin evidenced by migmatites formed at ca. 183Ma in a transpressive setting; (4) paroxysmal arc plutonic activity during the Jurassic (although the active magmatic arc was located farther south than the studied …